Raman and luminescence spectra of dianthracene at high pressures

Abstract

Raman spectra of single crystal and powdered samples of dianthracene have been recorded at temperatures from 77 to 410 K and at pressures to 32 kbar. The Raman and infrared spectra of dianthracene dispersed in KBr demonstrate the apparent stability of dianthracene under these conditions, contrary to other reports. At pressures above 10 kbar, However, a fluorescence background appeared with the Raman spectra excited with Ar and He–Ne lasers. This fluorescence is attributed to direct excitation of close-coupled sandwich-like dimer defects created and trapped in the crystal under pressure.